Gentoo Archives: gentoo-user

From: Mick <michaelkintzios@×××××.com>
To: gentoo-user@l.g.o
Subject: Re: [gentoo-user] Two local subnets and IPv6
Date: Tue, 08 Mar 2011 07:08:26
Message-Id: 201103080707.14998.michaelkintzios@gmail.com
In Reply to: [gentoo-user] Two local subnets and IPv6 by Nils Holland
1 On Monday 07 March 2011 23:54:18 Nils Holland wrote:
2 > Hi folks,
3 >
4 > well, this is not a strictly Gentoo-related question, but probably
5 > someone in here has an idea on this anyway.
6 >
7 > I currently have the following situation here:
8 > |Internet|
9 > |
10 > | (Dynamic public IPv4 address)
11 >
12 > DSL-Router
13 >
14 > | (192.168.178.1)
15 >
16 > -
17 >
18 > | (192.168.178.40, via WLAN)
19 >
20 > GentooBox1
21 >
22 > | (192.168.0.1, via Ethernet)
23 >
24 > -
25 >
26 > | (192.168.0.2...n, via Ethernet)
27 >
28 > GentooBox2...n
29 >
30 > The point in this setup is to have one machine with the best WLAN
31 > reception the Internet connection via WLAN, and serve as a router so
32 > that the other machines (many of which have problems receiving the
33 > weak WLAN signal) are connected via Ethernet and can reach the
34 > Internet via GentooBox1 (and communicate with one another at 100
35 > MBit/s or GigE speed). Works fine. Will do the job at least until
36 > I'll finally come around to pulling a cable between the DSL router in
37 > the floor below me and this room, which is the eventually planned
38 > solution.
39 >
40 > Now, however, IPv6 has entered the picture and makes things more
41 > difficult. At least I have not yet been able to find a way to make it
42 > work nicely in this scenario. Currently, I'm receiving IPv6 via a 6to4
43 > tunnel established directly by my DSL router. So the above diagram,
44 >
45 > with regard to IPv6, would look like this:
46 > |Internet|
47 >
48 > DSL-Router
49 >
50 > | (dynamic /48 based on its current public IPv4 address)
51 >
52 > -
53 >
54 > | (/64 address based on prefix and MAC of interface,
55 > |
56 > | assigned magically by the DSL router (I guess) (WLAN))
57 >
58 > GentooBox1
59 >
60 > | ??? (Ethernet)
61 >
62 > -
63 >
64 > | ??? (Ethernet)
65 >
66 > GentooBox2...n
67 >
68 > The ??? are where my problems start. I don't really have a clue what
69 > to do here. I probably shouldn't really manually assign IPv6 addresses
70 > to GentooBox1's and GentooBox2's Ethernet cards, since these wouldn't
71 > be worth much, as the prefix would change any time the IPv4 address
72 > that serves as a basis for the 6to4 address changes. I could also
73 > install radvd on GentooBox1, but the changing prefix would probably be
74 > a problem in that case as well, and I have the feeling that this
75 > wouldn't help me much anyway, as I'd probably have to add some routes
76 > to my DSL router's routing table for things to work - problem is, the
77 > DSL router will only let me manually add IPv4 routes, not IPv6 ones
78 > (at least with its official firmware).
79 >
80 > So, any ideas or pointers what I could do here? Of course, if I didn't
81 > have two subnets, things would be simple (then the DSL router could
82 > handle everything), but this just isn't the situation I have here
83 > right now. Bridging the Ethernet interface and the WLAN interface on
84 > GentooBox1 was my first idea actually, but doesn't seem to work with
85 > its WLAN NIC. And of course, any machines "behind" GentooBox2 could
86 > establish their own IPv6 tunnel connections, but ... well ... I the
87 > strong feeling that what I've been trying above should work as well
88 > ... somehow! ;-)
89
90 I have not tried this myself (my router won't do ipv6 yet) so you'll need to
91 try it out yourself. Instead of terminating the tunnel at your router,
92 forward it as is and terminate it at gentoo box 1. Then forward the ipv6
93 addresses from there for each of your clients. This means that the router
94 will no longer function as such and for all intends and purposes you can place
95 it in a fully bridged mode (no WAN IP address, no NAT-ing, no DHCP-ing.
96
97 Hope this helps.
98 --
99 Regards,
100 Mick

Attachments

File name MIME type
signature.asc application/pgp-signature

Replies

Subject Author
Re: [gentoo-user] Two local subnets and IPv6 Nils Holland <nhg@×××××.org>